revisiting tesla in the quantum random oracle model
play

Revisiting TESLA in the quantum random oracle model Selected - PowerPoint PPT Presentation

Revisiting TESLA in the quantum random oracle model Selected history of Fiat-Shamir style signatures from LWE or SIS Lyubashevsky 2012 Sigs via Fiat-Shamir Bai-Galbraith BLISS 2013 Short sigs Optimized DBGGOPSS 2014 Improvements,


  1. Revisiting TESLA in the quantum random oracle model

  2. Selected history of Fiat-Shamir— style signatures from LWE or SIS Lyubashevsky 2012 Sigs via Fiat-Shamir Bai-Galbraith BLISS 2013 Short sigs Optimized DBGGOPSS 2014 Improvements, fast implementation TESLA 2015 Tight security reduction, fast implementation ring-TESLA Now with rings, fast implementation 2016 TESLA# Improvements, fast implementation

  3. Selected history of Fiat-Shamir— style signatures from LWE or SIS Lyubashevsky 2012 Sigs via Fiat-Shamir Bai-Galbraith BLISS 2013 Short sigs Optimized DBGGOPSS 2014 Improvements, fast implementation TESLA This talk 2015 Tight security reduction, fast implementation ring-TESLA Now with rings, fast implementation 2016 TESLA# Improvements, fast implementation

  4. Preamble

  5. Given a forger... Sign Forger

  6. ...construct a P-solver Forger

  7. Parameter choice should account for the security reduction

  8. Tightness

  9. The quantum random oracle model (QROM) Hash

  10. When does ROM imply QROM? Boneh, Dagdelen, Fischlin, Lehmann, Schaffner, Zhandry

  11. Prior work on TESLA Lyubashevsky Sigs via Fiat-Shamir Bai-Galbraith BLISS Short sigs Optimized Reduction from LWE, SIS. DBGGOPSS Proof uses Forking Lemma. Improvements, fast implementation Non-tight, re-programming. ROM but not QROM. TESLA Tight security reduction, fast implementation ring-TESLA Reduction from LWE only. Now with rings, fast implementation Tight reduction in ROM. QROM via chameleon TESLA# hash functions. Improvements, fast implementation

  12. Our contributions (theoretical)

  13. Our contributions (practical)

  14. Summary of related work Katz, Wang Abdalla, Fouque, Lyubashevsky, Tibouchi Gentry, Peikert, Vaikuntanathan Boyen, Li

  15. “Lattice-based” crypto

  16. “Lattice-based” crypto

  17. Learning with Errors (LWE) (matrix version)

  18. TESLA key generation Pk: LWE yes-instance Sk: witness

  19. TESLA sign Zero-knowledge proof (S,E) + Fiat-Shamir

  20. TESLA sign: terminology

  21. TESLA verify

  22. Security theorem for TESLA

  23. Security theorem for TESLA Tightness: Scaling factor 1.

  24. Proof overview Sign Hash Forger

  25. Simulator Sign Hash classical quantum Simulator classical quantum

  26. Forger forges, even with a simulator Simulator Forger

  27. Forger + Simulator = LWE solver Simulator Forger

  28. Forger + Simulator = LWE solver

  29. Yes-instances: Signature simulator

  30. Yes-instances: Signature simulator Re-program a quantum oracle!

  31. Re-programming in TESLA

  32. No-instances: Good hash inputs

  33. Search through unstructured space

  34. Good hash inputs are rare

  35. Parameter sets

  36. Parameter sets

  37. Software

  38. Global A matrix?

  39. Proof approach Abdalla, Fouque, Lyubashevsky, Tibouchi

  40. Other tightly-secure LWE or SIS signatures (move to the end?)

  41. Comparison: LWE/SIS schemes

  42. Comparison: hash-based schemes

Recommend


More recommend